Vega is situated in the constellation Lyra, 25 light-years away from Earth, and it is the fifth brightest star in the sky. In 1983, astronomers discovered dust orbiting Vega, suggesting that it had a solar system. Vega was thought to be only a couple of hundred million years old, probably too young for any planets to have spawned life. However, new estimates show that Vega is significantly older than previously thought.
The scientists will publish their findings in The Astrophysical Journal Letters, but a preprint is available through arXiv. Astronomers have learned that the star spins fast, about once every 17 hours, which stirs up the star’s interior, and forces the surface composition to match the overall composition of the star. This means that scientists had been overestimating the star’s abundance of heavy metals, meaning that they overestimated its mass and underestimating its age. Massive stars evolve more slowly.
The astronomers studied Vega using the CHARA interferometer, an array of telescopes in California, and modeled the observations by using new computations of how fast-spinning stars age.
Vega is 2.15 times as massive as the sun, but between 625 million and 850 million years old. Suitable planets could have formed and sufficient time has elapsed for the development of primitive life.
Reference: “Resolving Vega and the inclination controversy with CHARA/MIRC” by J. D. Monnier, Xiao Che, Ming Zhao, S. Ekstrom, V. Maestro, J. Aufdenberg, F. Baron, C. Georgy, S. Kraus, H. McAlister, E. Pedretti, S. Ridgway, J. Sturmann, L. Sturmann, T. ten Brummelaar, N. Thureau, N. Turner and P. G. Tuthill, 15 November 2012, The Astrophysical Journal Letters.